In recent years, much research has been conducted into polymerization methods, with the aim of obtaining polymers that function as high value-added materials or highly functional materials that exhibit superior properties or function, and metal catalysts are frequently used in these polymerization reactions. In polymerization methods that use such metal catalysts, the metal catalyst remains within the produced polymer, and various methods have been proposed for recovering this metal catalyst (see patent references 1 to 5).
One example of the polymerization methods described above is a living radical polymerization method (for example, see non-patent reference 1), and in this type of living radical polymerization method, a copper complex or ruthenium complex is mainly used as the catalyst. An example of a method that has been proposed for removing the copper complex from a polymer produced using such a copper complex is a method that involves adding an organic acid (see patent reference 6).
[Patent Reference 1]
Japanese Unexamined Patent Application, First Publication No. Hei 8-141407
[Patent Reference 2]
Japanese Unexamined Patent Application, First Publication No. Hei 6-41652
[Patent Reference 3]
Japanese Unexamined Patent Application, First Publication No. 2000-239210
[Patent Reference 4]
Japanese Unexamined Patent Application, First Publication No. 2001-48824
[Patent Reference 5]
Japanese Unexamined Patent Application, First Publication No. 2002-249457
[Patent Reference 6]
Japanese Unexamined Patent Application, First Publication No. Hei 2003-147015
[Non-Patent Reference 1]
Chemistry Today, June 2001, pages 34 to 42.